Apparatus for preventing warp yarn breakage in a loom



Aug. 6, 1968 RIHEI NISHIKAWA 3,395,736

APPARATUS FOR PREVENTING WARP YARN BREAKAGE IN A LOOM llg- 6, 1968 Rn-u-:l NISHIKAWA 3,395,736

APPARATUS FOR PREVENTING WARP YARN BREAKAGE IN A LOOM Filed Sept. 16, 1966 6 Sheets-Sheet 2 ug- 6, 1968 RlHEl NISHIKAWA 3,395,736

APPARATUS FOR PREVENTING WARP YARN BREAKAGE IN A LOOM Filed Sept. 16, 1966 6 Sheets-Sheet 5 FIG. 3

Aug. 6, 1968 RIHEI NISHIKAWA APPARATUS FOR PREVENTING WARP YARN BREAKAGE IN A LOOM Filed Sept. 16, 1966 6 Sheets-Sheet 4 E hggHh/LIL Aug. 6, 1968 RIHEI NISHIKAWA 3,395,735

APPARATUS FOR PREVENTING WARP YARN BREAKAGE IN A LOOM Filed Sept. 16, 1966 6 Sheets-Sheet 5 Ug- 6, 1968 Rn-u-:l NISHIKAWA 3,395,736

APPARATUS FOR PREVENTING WARP YARN BREAKAGE IN A LOOM Filed Sept. 16, 1966 6 Sheets-Sheet 6 United States Patent O Mice 3,395,736 APPARATUS FOR PREVENTING WARP YARN BREAKAGE IN A LOOM Rihei Nishikawa, Kariya, Japan, assgnor to Toyoda Automatic Loom Works, Ltd., Kariya, Aichi Prefecture, Japan Filed Sept. 16, 1966, Ser. No. 579,873 Claims priority, application Japan, June 22, 1966, rt1/40,845 4 Claims. (Cl. 139-115) ABSTRACT F THE DISCLOSURE An apparatus for preventing Warp breakage when the shuttle in a loom fails to enter the shuttle box. The apparatus has a shuttle detector which is engageable with a latch means when the shuttle detector yfails to detect a shuttle in a shuttle box. The latch means releases a rst support lever which is pivoted to an effective position by a spring, and through a connecting rod pivots a second support lever carrying the tension roller for the warp yarns so as to pivot the second support lever in a direction to decrease the tension on the warp yarns.

This invention relates to an apparatus for preventing warp yarn breakage in a loom, and has for its object to provide an improved mechanism responsive to defective pick-ing motion and adapted to positively shift the tension roller to its ineffective position, for the purpose of avoiding undue tension and consequential breakage of the warp yarns when the shuttle is not properly boxed.

As is well known in the art of looms, when the shuttle is stopped at some point along the race and fails to enter the shuttle box, upon the next beating motion with the shuttle remaining in the shed, between the upper and lower rows of the warp yarns, there always occurs breakage of the warp yarns due to undue tension thereof. There have heretofore been proposed many devices for removing such disadvantage.

In one of the conventional devices for this purpose, a mechanism responsive to the absence of the shuttle from the shuttle box is employed for stopping the `driving mechanism of the loom and, at the same time, for positively stopping the race coming toward the cloth fell, thereby avoiding the insertion of the shuttle between the cloth fell and the reed so as to prevent breakage of the warp yarns. In such a device, however, positively yand quickly stopping the forward motion of the race is not so easy, because of the great inertia of the driving mechanism and of the forward motion of the race, so that it is very difcult to ycompletely iinish the stopping of all parts before the shuttle stopped on the Arace engages the cloth fell together with the race. Especially in a high speed loom, it will be practically impossible to stop the operation of the loom within the predetermined period of time. Consequently, such a conventional device for preventing breakage of warp yarns is not practical.

Another device has been proposed in which there is provided a reed adapted to be turned around the upper or lower edge thereof when it is acted upon by the improperly positioned shuttle, so as to prevent warp yarn breakage. In such a device, however, the warp yarns are subjected to undesirable fatigue, because of the fact that the warp yarns must absorb the inertia of the moving reed.

The principal object of the present invention is to overcome the above mentioned drawbacks inherent in the conventional devices and, according to the present invention, a mechanism responsive to absence of the shuttle from the shuttle box and adapted to positively shift the tension roller into its ineffective position, so that the Warp yarns are slackened without any load being placed there- 3,395,736 Patented Aug. 6, 1968 on. Thus, it will be understood that the device according to the present invention is applicable to a high speed loom.

Other objects and advantages will become more fully apparent as reference is had to the accompanying drawings wherein the present invention is illustrated. In the drawings:

FIG. 1 is a side elevation view, partly in section of a loom with the apparatus according to the present invention rand showing the tension roller in its ineffective position where the shuttle is correctly positioned in the shuttle box;

FIG. 2 is a view similar to FIG. l with the tension r-oller retracted;

FIG. 3 is a somewhat enlarged perspective view of details of the apparatus shown in FIG. l;

FIG. 4 is a side elevation view, partly in section, of a second embodiment of the present invention showing the tension roller in its ineffective position;

FIG. 5 is a view similar to FIG. 4, showing the parts in the operative positions;

FIG. 6 is a side elevation view, partly in section, of a third embodiment of the present invention; and

FIG. 7 is a somewhat enlarged perspective view of the apparatus shown in FIG. 6.

Referring to FIGS. l, 2 and 3, in which the apparatus according to the present invention is shown as applied to a loom of the type having shuttle boxes which are separable from the race, S designates a shuttle adapted to be received in the shuttle boxes disposed on opposite sides of the loom. Each shuttle box has the usual swell 1 forming the rear wall thereof, which swell serves as a shock absorber. A shuttle detector lever 2 is pivotally mounted at 3 on the machine frame F, and it has at its upper end an adjustable screw 4 retained in contact with the outer face of said swell 1 through the bias of a spring 5. The lower end of the detector lever 2 is connected by means of a link 6 to the mid Apoint of a catch lever 7, the upper end of which is pivotally connected to a rockable member 8 having a pivot 8 on which it is mounted. A rotary cam 9 is rotatably mounted on the loom lever 10 pivoted at 11 and having a cam follower roller 12 is operatively associated with said cam 9. The hook lever 10 is provided at its free end with a hook 10. The hook lever 10 is adapted to be turned upwardly by means of the cam 9 immediately after the shuttle S is received in the shuttle Ibox. If the shuttle fails to be received in the shuttle box, or is late being received in the shuttle box, the shuttle detector 2 detecting said defective picking motion will be oscillated in the counterclockwise direction, whereby the lower end 7 of the catch lever 7 will be pushed into the path of the upward movement of the hook 10' of the hook lever 10. Thus, the catch lever 7 is lifted and, thereby, the rockable member 8 is turned around the pivot 8 in the counterclockwise direction. Said rockable member 8 is connected through a rod 13 with one end of a bellcrank lever 14 pivoted at 14. The other end of said bellcrank lever abuts a hook 15 xed on a support lever 16 which is pivoted at 16' on the machine frame F and is biased b-ackwardly (to the right in FIG. 1) by means of a spring 17. The support lever 16 has a 'bore 18 therethrough, through which a horizontal rod 19 is loosely passed. The screw threaded lefthand end 19 of the rod 19 has an adjustable stop 20 abutting against the front face (in FIG. l the left face) of the lever 16, and the other end of the rod 19 is pivotally mounted on a movable bracket 21. Disposed opposiely to the lever 16, there is a second vertical support lever 22 pivoted at 22 to the machine frame F. A spring 23 is connected at its one end to the rear end of the rod 19, and at the other end to a second bracket 24 mounted on the upper end of said second lever 22, the spring 23 tending to pull the second lever 22 forwardly (to the left in FIG. l). To

the lower portion of the second lever 22, there is connected by means of a link 25 a tension roller TR which is normally biased forwardly by the action of said spring 23. The tension of the spring 23 and, consequent-ly the tension on the warp yarns W, may be varied by adjusting the position of the stopl 20 on the rod 19. A second horizontal rod 26 is pivotally connected to the support lever 16, and the other end thereof is loosely passed through a bore 27 in the second support lever 22. At the rear end portion of said rod 26, at a position in the vicinity of the inner edge of the lever 22, there is secured an adjustable stop 26', the distance between the lever 16 and said stop 26 -being somewhat shorter than the distance between the lever 16 and the second lever 22 along the rod 19 as determined by the adjustable stop 20.

In the drawings, the warp yarns W taken off from the yarn beam B are passed around the guide roller 28, the said tension roller TR, and the guide roller 29 toward the front, being subjected to the shedding motion, and the woven cloth C is passed through abreast beam 30, a take up roller 31, guide rollers 32, 33 and 34, and wound upon a cloth beam 35 in the conventional manner.

The operation of the above mentioned apparatus is as follows: When the running shuttle S arrives within the shuttle box at the predetermined correct time, the upper end of the shuttle detector 2 is pushed rearwardly by the action of the swell 1 which has been pressed outwardly by the entering7 shuttle, whereby the detector 2 oscillating in clockwise direction will pull the catch lever 7 forwardly by means of the link 6, so that the lower end of said catch lever 7 is kept out of the path of upward movement of the hook 10 of the hook lever or cam follower lever 10, as shown in FIG. l. Consequently, the bellcrank lever 14 or the latch member will not he influenced by the upward movement of the hook 10' of the cam follower lever 10, and it is held in its normal position engaging the hook 15 on the support lever 16. Thus, the lever 16 is kept in a forwardly inclined position against the action of the spring 17, as shown in FIG. l, so that the tension of the spring 23 is effective to pull the tension roller TR forwardly, and the warp yarns 'W are held under the requisite tension for the weaving operation.

Now, when the shuttle S stops on its way on the race, failing to correctly enter the shuttle box, as caused by a defective picking, the shuttle detector 2 will be oscillated in the counterclockwise direction by the action of the spring 5, so that the lower end 7 of the catch lever 7 will be pushed backwardly by the link 6 and will come into the path of upward movement of the hook 10 of the cam follower lever 10. Thus, upon the upward movement of the hook '10' actuated by the cam 9, the rockable member 8 will be turned in the counterclockwise direction around the pivot 3', and thereby the latch member 14 will be oscillated in the clockwise direction around the pivot 14', disengaging the front end thereof from: the hook 15 :on the lever 16. The lever 16 thus released will be tilted backwardly by the action of the spring 17. The stop 26 on the rod 26 will push the second vertical lever 22 backwardly, lso that the tension roller TR is shifted lbackwardly to irelease the tension of the warp yarns W by an amount corresponding to the displacement of the tension roller. In view of the above, even if a beating motion occurs while the shuttle is being held in the shed, between the upper and lower warp yarns, there is no danger of causing any Warp yarn breakage.

Referring to FIGS. 4 and 5, showing the second embodiment of the present invention as applied to a conventional type of the loom, wherein the shuttle boxes and the race are ixedly connected, due to the identity and equivalency of the major portion of the structure illustrated in this embodiment and of that illustrated in FIGS. 1 to 3, this embodiment will be described by corresponding reference numerals plus 100 for the sake of clarity, and some description will be omitted for the sake of avoiding repetition. The shuttle S is adapted to run along the race mounted on a slay sword 51 which is swingable around a shaft 52 and actuated by a crank 53 of the loom. A swell 101 forms a part of the shuttle box and serves as a shock absorber for the running shuttle. A shuttle detector 102 in the form of a bellcrank lever is biased by means of a spring in a counterclockwise direction. The upper end of said detector 102 has an adjustable screw 104 abutting the rear side of the swell 101. When the shuttle S correctly enters the shuttle box, the upper end of the detector 102 is held in the pushed out position by said swell 101, the lower arm of the detector being turned upwardly against the action of the spring 105 as shown in FIG. 4. On the other hand, when the shuttle stops on the race, failing to enter the shuttle box, the detector 102 is turned in the counterclockwise direction by the action of the spring 105 (FIG. 5), and the said lower arm will be engaged by a hook 54' formed at the free end of a rod 54 which is slidably mounted on the machine frame F so that upon the forward swing of the slay sword 51 (to the left in FIG. 4) said rod 54 will be pulled forwardly. The other end of the rod 54 is connected to one arm of a bellcrank lever 108 pivoted at 108', and the other arm of the lever 108 is connected through a rod 113 to the rear end of a catch lever or a -latch member 114 which abuts at the other end against a hook 115 secured to the support lever 116. Normally, said catch lever 114 is held substantially in a horizontal position, and the lever 116 is in the counterclockwise turned position (FIG. 4). Upon the forward movement of the rod 54, the hook 115 is released from the catch lever 114 and the lever 116 is caused to turn backwardly around the pivot 116 by the action of the spring 117 (FIG. 5). The operation of the warp yarn tensioning device composed of the support levers 116 and 122 is substantially the same as described above with reference to the embodiment shown in FIGS. 1 to 3. The second support lever 122 in the form of a bellcrank lever is normally held erect as shown in FIG. 4, and the tension roller TR is in its effective position for tensioning the warp yarns W. Upon the defective picking of the shuttle S, the rod 54 is pulled forwardly by the engagement of the hook 54 and the lower end of the detector 102, the support lever 116 is allowed to come to its vertical position, and the second support lever 122 turns backwardly, so that the tension roller is retracted to its ineffective position as shown in FIG. 5.

Referring to FIGS. 6 and 7, there is shown the third embodiment of the present invention, in which the device for exerting warp tensioning force comprises a weight instead of the spring. A weight lever 61 is pivotally mounted at 62 on the vertical support lever 63 which is pivoted at 63 on the rear part of the loom frame. The axle of the tension roller TR is rotatably engaged with the rear arm 61 of the weight lever, and on the front arm 61 of the weight lever there is movably mounted a weight 64, whereby the tension roller TR is lifted and caused to exert the requisite tension to the warp yarns W. A guide roller 129 as well as the tension roller TR are journalled in an inclined bar 65 having the lower end connected to one end of a lever 66. The other end of lever 66 is in contact with a rotary cam 67 on a shaft 68 (FIG. 6) and, by the oscillation of said rod 66 caused by said rotary cam 67, the warp tension can be maintained substantially constant during the shedding motion. A spring 69 connected to the lower end of said vertical lever 63 has a tendency to urge the lever 63 forwardly. However, said forward oscillation is normally prevented by a catch lever or a latch member 70 which engages with a hook 71 secured to the lever 63. A rod 72 is connected to the lower arm of said latch member 70.

When the shuttle does not correctly enter the shuttle box due to a defective picking, the rod 72 is pulled forwardly as controlled and actuated by the shuttle detector as mentioned above, and thereby the Alatch member 70 will be disengaged from the hook 71, so that the vertical 5 lever 63 is turned forwardly by the action of the spring 73. Consequently, the tension roller TR supported on the arm 61 is shifted forwardly and downwardly, thereby slackening the warp yarns W.

From the foregoing, it will be seen that according to the present invention, by the provision of the shuttle detector and the associated mechanism, the tension roller is shifted to its ineffective position in case of defective picking motion. In contradistinction to the conventional device in which the shifting of the tension roller is effected depending upon the tension of the warp yarns, according to the present invention the tension roller is positively retracted to its ineffective position by the mechanism responsive to the absence of the shuttle in the shuttle box, so that undesirable fatigue of the warp yarns and consequential breakage thereof may be prevented.

What I claim is:

1. In a loom having shuttle boxes with swells, and a warp tension roller which acts to tension the warp, an apparatus for preventing warp breakage comprising a shuttle detector associated with each shuttle box and pivotally mounted on the loom with its one end abutting a swell of the respective shuttle box, a first spring connected to the shuttle detector biasing one end thereof against the swell, a first oscillatable support lever, latch means engageable with said first support lever for holding said first support lever in an ineffective normal position, a second spring coupled to said first support lever and biasing said first support lever toward an effective position, said latch means being controlled through intermediate means by the other end of said shuttle detector when the shuttle fails to be boxed properly at the time of beating up to release said first support lever and permit same to swing to its effective position, a second oscillatable support lever on which the tension roller is mounted, a rod operatively connecting said first support lever and said second support lever and operable to move the second support lever and tension roller in a direction to reduce tension in said warp when said latch is released through the bias of said second spring moving said first support lever to its effective position.

2. An apparatus as claimed in claim 1 further comprising tension adjusting means coupled between said support levers and comprising a spring coupled to one support lever and a rod connected to the free end of the spring and adjustably coupled to the other support lever, whereby the tension of said spring can be adjusted for moving the support levers toward each other for changing the tension exerted by the tension roller on the warp yarns.

3. An apparatus as claimed in claim 1 in which the loom has a slay sword and said shuttle detector is mounted on the slay sword, said first spring pivoting the shuttle detector to move the end thereof remote from the end contacting the swell into the path of said latch means, and said latch means being moved to release said first support lever by the movement of the slay sword.

4. In a loom having shuttle boxes with swells, and a warp tension roller which acts to tension the warp, an apparatus for preventing warp breakage comprising a shuttle detector associated with each shuttle box and pivotally mounted on the loom with one end abutting a swell of the associated shuttle box, a first spring connected to the shuttle detector and biasing one end thereof against the swell, a first oscillatable support lever, latch means engageable with said first support lever for holding said first support lever in a normal operating position, a second spring coupled to said first support lever and biasing said first support lever toward an effective position in which the tension on the warp is reduced, intermediate means operatively connecting said latch means with the other end of said shuttle detector to control same when lthe shuttle fails to release said latch means and per- Vmit the `first lever to swing to its effective position, a second oscillatable lever pivotally mounted on said first support lever, said second oscillatable lever carries on one end thereof the tension roller and on the other end thereof an adjustably mounted weight, said weight acting to pivot the second lever in a direction to increase the tension applied by the tension roller to the warp, whereby when said shuttle detector acts to operate said latch means the first support lever, the second lever and the tension roller are moved in the tension releasing direction.

References Cited UNITED STATES PATENTS 731,622 6/1903 Roper 139-115 1,532,668 4/1925 Baker 139-115 2,515,389 7/1950 Angus et al 139-115 FOREIGN PATENTS 408,087 4/1934 Great Britain.

HENRY S. JAUDON, Primary Examiner. 

